CN114690109A - Test device and test method for converter valve thyristor voltage monitoring unit - Google Patents

Abstract

The embodiments of the present invention relate to a testing device and method for a thyristor voltage monitoring unit of a converter valve. The device includes a main control module, a testing power supply module and a communication module; the input of the testing power supply module is connected to the AC input power supply, and the output is connected to the commutation under test. a valve thyristor voltage monitoring unit; the communication module is connected in communication with the converter valve thyristor voltage monitoring unit, receives the back-check signal output by the converter valve thyristor voltage monitoring unit, and collects the voltage values at both ends of the thyristor corresponding to the back-check time; the main control The module is respectively connected to the test power supply module and the communication module, receives the back-check signal and voltage value transmitted by the communication module, tests whether the voltage monitoring unit of the thyristor of the converter valve is faulty, and locates the fault. The technical solution provided by the embodiment of the present invention can realize the full function test of high and low voltage of the thyristor voltage monitoring unit under the voltage of 220V, the test voltage level is low, and the equipment volume is small.

Description

Test device and test method for converter valve thyristor voltage monitoring unit

technical field

Embodiments of the present invention relate to the technical field of high-voltage direct current power transmission, and in particular, to a testing device and a testing method for a thyristor voltage monitoring unit of a converter valve.

Background technique

The thyristor voltage monitoring unit (TVM) of the HVDC converter valve is the core component of the light-controlled converter valve, and its stability and accuracy affect the safe and reliable operation of the converter valve. Before the thyristor voltage monitoring unit is put into use, it must be fully functionally tested.

At present, there are only thyristor-level unit testers on site at the converter station, which can only perform low-voltage functional tests on the entire thyristor stage, but cannot perform high-voltage tests, and cannot perform fault location. It is limited by imported equipment, and the maintenance cycle is long. The spare parts of the thyristor voltage monitoring unit of the station are regularly inspected, which has caused great inconvenience to the operation and maintenance of the DC transmission system.

SUMMARY OF THE INVENTION

Based on the above-mentioned situation in the prior art, the purpose of the embodiments of the present invention is to provide a test device and a test method for a thyristor voltage monitoring unit of a converter valve, which can realize the full function test of high and low voltage of the thyristor voltage monitoring unit under a voltage of 220V. The low voltage level and the small size of the equipment can meet the needs of engineering applications, and can realize the offline test and fault location of the thyristor voltage monitoring unit, which greatly improves the efficiency and safety of the thyristor voltage monitoring unit test.

In order to achieve the above object, according to an aspect of the present invention, a test device for a thyristor voltage monitoring unit of a converter valve is provided, which includes a main control module, a test power supply module and a communication module; wherein,

The input of the test power module is connected to the AC input power supply, and the output is connected to the thyristor voltage monitoring unit of the converter valve under test, so as to provide working power and monitoring power for the thyristor voltage monitoring unit of the converter valve under test;

The communication module is in communication connection with the thyristor voltage monitoring unit of the converter valve, and receives the check signal output by the thyristor voltage monitoring unit of the converter valve;

The main control module is respectively connected to the test power module and the communication module, controls the test power module through a relay, collects and processes the voltages at both ends of the converter valve thyristor, and receives the communication module The transmitted back-check signal is used to test whether the thyristor voltage monitoring unit of the converter valve is faulty, and to locate the fault of the thyristor voltage monitoring unit of the converter valve.

Further, the test power supply module includes an energy acquisition power supply unit and a detection power supply unit.

Further, the device further includes a relay switching module, and the energy acquisition power supply unit and the detection power supply unit are switched through the relay switching module.

Further, the energy taking power supply unit includes a first isolated power supply circuit and an equivalent energy taking capacitor, and the first isolated power supply circuit and the equivalent energy taking capacitor are connected in series.

Further, the detection power supply unit includes a second isolated power supply circuit and a current limiting resistor, and the second isolated power supply circuit and the current limiting resistor are connected in series.

Further, the communication module includes a logic control unit and a photoelectric conversion unit;

The logic control unit includes a control chip and its peripheral circuits for data acquisition and processing;

The photoelectric conversion unit includes a photoelectric conversion circuit for converting the received optical signal into an electrical signal.

Further, the main control module performs fault location of the thyristor voltage monitoring unit of the converter valve according to the results of each test item of positive voltage detection, negative voltage detection and BOD detection.

According to another aspect of the present invention, there is provided a method for testing using the testing device according to the first aspect of the present invention, comprising:

Connect the equivalent energy-acquisition capacitor of the energy-acquisition power supply unit to the energy-acquisition power supply terminal of the thyristor voltage monitoring unit of the converter valve, and connect the current limiting resistor of the detection power supply unit to the voltage detection terminal of the thyristor voltage monitoring unit of the converter valve. Measure the thyristor voltage monitoring unit of the converter valve and apply alternating current;

Receive the checkback signal generated by the thyristor voltage monitoring unit and the voltage value at both ends of the thyristor at the checkback time, and judge whether the thyristor voltage monitoring unit is normal according to the signal pulse width of the checkback signal and whether the voltage value meets a preset threshold.

Further, the checkback signal includes a positive checkback signal, a negative checkback signal and an overvoltage checkback signal;

If the pulse widths of the positive check signal, the negative check signal and the overvoltage check signal, and the voltage values at both ends of the thyristor at the time of check meet the preset thresholds, it is judged that the thyristor voltage monitoring unit is normal; otherwise, it is judged that the thyristor voltage monitoring unit is normal. The thyristor voltage monitoring unit has failed.

Further, it also includes: when a fault occurs in the thyristor voltage monitoring unit, locating the fault.

To sum up, the embodiments of the present invention provide a test device and method for a thyristor voltage monitoring unit of a converter valve, the device includes a main control module, a test power module and a communication module; the input of the test power module is connected to an AC input a power supply, the output is connected to the thyristor voltage monitoring unit of the converter valve under test, and provides working power and monitoring power for the thyristor voltage monitoring unit of the converter valve under test; the communication module is connected in communication with the thyristor voltage monitoring unit of the converter valve, and receives the the back-check signal output by the converter valve thyristor voltage monitoring unit, and collect the voltage values at both ends of the thyristor corresponding to the converter valve thyristor voltage monitoring unit at the time of back-check; the main control module is respectively connected to the test power module and the communication module, In order to perform input and output control and data acquisition on the test power module, and receive the back-check signal and voltage value transmitted by the communication module, test whether the thyristor voltage monitoring unit of the converter valve is faulty, and perform fault location. The technical solution provided by the embodiment of the present invention solves the problem of lack of effective means for monitoring the voltage of the thyristor voltage in the prior art, and can realize the full function test of the high and low voltage of the thyristor voltage monitoring unit under the voltage of 220V, and the test voltage level is low, The device is small in size, can meet the needs of engineering applications, and can realize offline testing and fault location of the thyristor voltage monitoring unit, which greatly improves the efficiency and safety of the thyristor voltage monitoring unit test.

Description of drawings

1 is a system structure diagram of a testing device for a thyristor voltage monitoring unit of a converter valve provided by an embodiment of the present invention;

2 is a schematic diagram of the circuit connection of the converter valve thyristor voltage monitoring unit in the converter valve system;

Figure 3 is a schematic diagram of the thyristor voltage monitoring unit (TVM) voltage monitoring function.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the specific embodiments and the accompanying drawings. It should be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention. Also, in the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concepts of the present invention.

The thyristor voltage monitoring unit (TVM) of the HVDC converter valve is the core component of the light-controlled converter valve, and its stability and accuracy affect the safe and reliable operation of the converter valve. In practical engineering applications, each thyristor stage needs to install a thyristor voltage monitoring unit to ensure the DC voltage equalization between the series connected thyristors, monitor the voltage at both ends of the thyristor, and generate a feedback signal. When the forward voltage at both ends of the thyristor exceeds the forward threshold value, the thyristor voltage monitoring unit generates a 6-8μs wide forward check pulse to the valve control device to check the blocking ability of the thyristor and whether the thyristor can be triggered and turned on; when the thyristor two When the negative voltage at the terminal exceeds the negative threshold, the thyristor voltage monitoring unit generates a 2-4μs wide negative check pulse to the valve control device to check whether the thyristor current crosses zero; when the voltage at both ends of the thyristor exceeds the positive overvoltage protection threshold When the value is set, the thyristor voltage monitoring unit generates a 10-15μs wide overvoltage protection check pulse to the valve control device to check whether the thyristor has a forward overvoltage protection trigger. Before the thyristor voltage monitoring unit is put into use, it must be fully functionally tested. However, there is currently a lack of effective means for comprehensive functional testing of the thyristor voltage monitoring unit.

In view of the above situation, an embodiment of the present invention provides a testing device for a thyristor voltage monitoring unit of a converter valve, so as to realize efficient testing of the thyristor voltage monitoring unit. The technical solutions of the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. An embodiment of the present invention provides a test device for a thyristor voltage monitoring unit of a converter valve. FIG. 1 shows a system structure diagram of the test device, including a main control module, a test power module and a communication module.

The input of the test power module is connected to the AC input power supply, such as the AC power input of the mains, and the output is connected to the voltage monitoring unit of the thyristor of the converter valve under test, which provides the working power and the monitoring power for the voltage monitoring unit of the thyristor of the converter valve under test. The test power supply module includes an energy acquisition power supply unit and a detection power supply unit, the energy acquisition power supply unit includes a first isolated power supply circuit and an equivalent energy acquisition capacitor, and the first isolated power supply circuit and the equivalent energy acquisition capacitor are connected in series. The detection power supply unit includes a second isolated power supply circuit and a current limiting resistor, and the second isolated power supply circuit and the current limiting resistor are connected in series. The device may further include a relay switching module, and the energy-acquisition power supply unit and the detection power supply unit are switched through time sequence control of the relay switching module.

The communication module is connected in communication with the thyristor voltage monitoring unit of the converter valve, and receives the checkback signal output by the thyristor voltage monitoring unit of the converter valve. The communication module includes a logic control unit and a photoelectric conversion unit, and the logic control unit can be realized by FPGA. The logic control unit includes a control chip and its peripheral circuits for data acquisition and processing; the photoelectric conversion unit includes a photoelectric conversion circuit for converting received optical signals into electrical signals. The main control module is respectively connected to the test power module and the communication module, controls the test power module through a relay, collects and processes the voltages at both ends of the converter valve thyristor, and receives the communication module The transmitted back-check signal is used to test whether the thyristor voltage monitoring unit of the converter valve is faulty, and to locate the fault of the thyristor voltage monitoring unit of the converter valve. The main control module mainly locates the fault of the thyristor voltage monitoring unit of the converter valve according to the results of the positive voltage detection, the negative voltage detection and the BOD detection of each test item.

In addition, the device may also include other protection function circuits, for example, an EMI module is arranged between the test power supply module and the commercial power input, so as to filter the electromagnetic interference of the input AC power supply.

The circuit connection diagram of the converter valve thyristor voltage monitoring unit in the converter valve system is shown in Figure 2. In FIG. 2, a thyristor voltage monitoring unit (TVM) is connected in parallel at both ends of the thyristor T to be monitored, for monitoring the voltage across the thyristor. Capacitor C and resistor R form the damping loop of the converter valve, which is used to achieve dynamic voltage equalization of series-connected thyristors and suppress commutation overshoot. A thyristor voltage monitoring unit (TVM) communicates with the valve control device via an optical cable. The thyristor voltage monitoring unit (TVM) includes a forward voltage detection module, a negative voltage detection module, an overvoltage detection module, a forward energy storage module, a negative energy storage module, a light emission module, etc. The collected data of the voltage value can locate the faulty module of the thyristor voltage monitoring unit (TVM). Figure 3 shows the schematic diagram of the voltage monitoring function of the thyristor voltage monitoring unit (TVM). As shown in Figure 3, when the negative voltage across the thyristor exceeds the negative threshold, the TVM generates a 2-4s wide negative back check. Pulse to the light receiving board of the valve control equipment, check whether the thyristor current crosses zero; when the forward voltage across the thyristor exceeds the forward threshold value, the TVM generates a 6-8s wide forward check pulse to the light receiving of the valve control equipment board, check the blocking ability of the thyristor and whether the thyristor can trigger conduction; when the voltage across the thyristor exceeds the forward overvoltage protection value, the TVM generates a 10-15s wide overvoltage protection check pulse to the light receiving of the valve control device board, and check whether the thyristor will trigger the forward overvoltage protection.

The embodiment of the present invention also provides a method for testing by using the test device provided in the above embodiment, comprising the following steps:

S102. Connect the equivalent energy-capacitor of the energy-capturing power supply unit to the energy-capturing power supply terminal of the converter valve thyristor voltage monitoring unit, and connect the current limiting resistor of the detection power supply unit to the voltage detection terminal of the converter valve thyristor voltage monitoring unit, and at the same time Apply alternating current to the thyristor voltage monitoring unit of the converter valve to be tested;

S104. Receive a checkback signal generated by the thyristor voltage monitoring unit and the voltage value at both ends of the thyristor at the checkback time, and determine whether the thyristor voltage monitoring unit is normal according to the signal pulse width of the checkback signal and whether the voltage value meets a preset threshold. Wherein, the recheck signal includes positive recheck signal, negative recheck signal and overvoltage recheck signal; if the pulse width of the positive recheck signal, negative recheck signal and overvoltage recheck signal, and When the voltage values at both ends of the thyristor meet the preset threshold value at the detection time, it is judged that the thyristor voltage monitoring unit is normal; otherwise, it is judged that the thyristor voltage monitoring unit is faulty.

Can also include steps:

S106. When a fault occurs in the thyristor voltage monitoring unit, locate the fault. The faulty module of the thyristor voltage monitoring unit (TVM) can be located according to the data collected by the test device on the back-checked signal and the voltage value.

To sum up, the embodiments of the present invention relate to a testing device and method for a thyristor voltage monitoring unit of a converter valve, the device includes a main control module, a testing power supply module and a communication module; the input of the testing power supply module is connected to an AC input power supply , the output is connected to the thyristor voltage monitoring unit of the converter valve under test to provide working power and monitoring power for the thyristor voltage monitoring unit of the converter valve under test; the communication module is connected in communication with the thyristor voltage monitoring unit of the converter valve, and receives the The return inspection signal output by the thyristor voltage monitoring unit of the converter valve is collected, and the voltage value at both ends of the thyristor corresponding to the voltage monitoring unit of the thyristor of the converter valve is collected at the time of the return inspection; the main control module is respectively connected to the test power supply module and the communication module to Input and output control and data acquisition are performed on the test power module, and the back-check signal and voltage value transmitted by the communication module are received to test whether the thyristor voltage monitoring unit of the converter valve is faulty, and to locate the fault. The technical solution provided by the embodiment of the present invention solves the problem of the lack of effective means for monitoring the voltage of the thyristor voltage in the prior art, and can realize the full function test of the high and low voltage of the thyristor voltage monitoring unit under the voltage of 220V, and the test voltage level is low, The device is small in size, can meet the needs of engineering applications, and can realize offline testing and fault location of the thyristor voltage monitoring unit, which greatly improves the efficiency and safety of the thyristor voltage monitoring unit test.

It should be understood that the above-mentioned specific embodiments of the present invention are only used to illustrate or explain the principle of the present invention, but not to limit the present invention. Therefore, any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and scope of the present invention should be included within the protection scope of the present invention. Furthermore, the appended claims of this invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalents of such scope and boundaries.

Claims (10)

1. a test device for a converter valve thyristor voltage monitoring unit, characterized in that it comprises a main control module, a test power supply module and a communication module; wherein, The input of the test power module is connected to the AC input power supply, and the output is connected to the thyristor voltage monitoring unit of the converter valve under test, so as to provide working power and monitoring power for the thyristor voltage monitoring unit of the converter valve under test; The communication module is in communication connection with the thyristor voltage monitoring unit of the converter valve, and receives the check signal output by the thyristor voltage monitoring unit of the converter valve; The main control module is respectively connected to the test power module and the communication module, controls the test power module through a relay, collects and processes the voltages at both ends of the converter valve thyristor, and receives the communication module The transmitted back-check signal is used to test whether the thyristor voltage monitoring unit of the converter valve is faulty, and to locate the fault of the thyristor voltage monitoring unit of the converter valve. 2 . The device according to claim 1 , wherein the test power supply module comprises an energy acquisition power supply unit and a detection power supply unit. 3 . 3 . The device according to claim 2 , wherein the device further comprises a relay switching module, and the energy acquisition power supply unit and the detection power supply unit are switched through the relay switching module. 4 . 4 . The device according to claim 3 , wherein the energy obtaining power supply unit comprises a first isolated power supply circuit and an equivalent energy obtaining capacitor, and the first isolated power supply circuit and the equivalent energy obtaining capacitor are connected in series. 5 . 5 . The device according to claim 3 , wherein the detection power supply unit comprises a second isolated power supply circuit and a current limiting resistor, and the second isolated power supply circuit and the current limiting resistor are connected in series. 6 . 6. The device according to claim 4 or 5, wherein the communication module comprises a logic control unit and a photoelectric conversion unit; The logic control unit includes a control chip and its peripheral circuits for data acquisition and processing; The photoelectric conversion unit includes a photoelectric conversion circuit for converting the received optical signal into an electrical signal. 7 . The device according to claim 1 , wherein the main control module performs fault location of the thyristor voltage monitoring unit of the converter valve according to the results of each test item of positive voltage detection, negative voltage detection and BOD detection. 8 . 8. A method for testing using the test device according to any one of claims 1-7, characterized in that, comprising: Connect the equivalent energy-acquisition capacitor of the energy-acquisition power supply unit to the energy-acquisition power supply terminal of the thyristor voltage monitoring unit of the converter valve, and connect the current limiting resistor of the detection power supply unit to the voltage detection terminal of the thyristor voltage monitoring unit of the converter valve. Measure the thyristor voltage monitoring unit of the converter valve and apply alternating current; Receive the checkback signal generated by the thyristor voltage monitoring unit and the voltage value at both ends of the thyristor at the checkback time, and judge whether the thyristor voltage monitoring unit is normal according to the signal pulse width of the checkback signal and whether the voltage value meets a preset threshold. 9 . The method according to claim 8 , wherein the rechecking signal comprises a positive rechecking signal, a negative rechecking signal and an overvoltage rechecking signal; 9 . If the pulse widths of the positive check signal, the negative check signal and the overvoltage check signal, and the voltage values at both ends of the thyristor at the time of check meet the preset thresholds, it is judged that the thyristor voltage monitoring unit is normal; otherwise, it is judged that the thyristor voltage monitoring unit is normal. The thyristor voltage monitoring unit has failed. 10. The method of claim 9, further comprising: when a fault occurs in the thyristor voltage monitoring unit, locating the fault.

Images